Coin operated kiddie ride



March 16, 1965 Gy w. REWE Em. 3,173,686

COIN OPERATED KIDDIE RIDE 4 'sheets-sheet 1 Filed Julr 18, 1962 JIJ ILT...

INVENTOR5 March 16, 1965 G. w. RETTIE ETAL 3,173,686

COIN OPERATED KIDDE RIDE Filed July 18, 1962 Q 33 v` E75.:

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4 Sheets-Sheet 2 March 16, 1965 G. w. RETTIE ETAL 3,173,686

COIN OPERTED KIDDIE RIDE Filed July 18, 1962 4 Sheets-Sheet 3 'RL b RLC RLC

March 16, 1965 l G, w, RET-11E ETAL 3,173,686

COIN OPERATED KIDDIE RIDE Filed July 18, 1962 4 Sheets-Shes?l 4 J INVENTORS ffw/ United States Patent O 3,173,686 G01N OPERATED KIDDIE RIDE George W. Rettie and Robert D. Hotchkiss, both of SE. 6th St., llfiami, Fla. Filed .luiy 18, 1962, Ser. No. 210,713 5 Claims. (Ci. 272-17) This invention relates to mechanical devices commonly referred to as Coin Operated Kiddie Rides. These devices have simulated bodies which are reduced models of boats, rocketships, submarines, space capsules, automobiles, etc. They have these factors in common: operation is started by the deposit of a coin and ended by action of a timing device associated with the electrical current used to activate the ride.

The primary object of this invention is to provide mechanical means to impart motion to the movable bodies which are reduced size models of the types listed which simulates movements of the actual devices.

It is also an obiect of this invention to provide a mechanical device which permits the mounting of various bodies of the types listed, suspended between two rigid stanchions in such a manner that movements having two distinct relationships to the movements of actual devices can be imparted. The first is that movement which a motor driven means imparts to simulate the fixed cycle of more or less vertical motion of an actual device. The second is that movement effected by manually operated control means to effect displacement of the body from the vertical, simulating movement of the actual device when effected by control of the operator.

It is also an object of this invention to provide motor driven and manually operated means of such nature that, in addition to, and without interfering with, the motion imparted by the motor driven means, the passenger can controllably cause the device to move in a manner which simulates the movement of the actual device in response to control by the operator.

Itis also an object of this invention to provide mechanical means to impart motion to as many devices as possible of the class described, with the identical parts assembled in varied relationships, so that the resulting movement matches as nearly as possible 'the movements of the actual device.

It is also an object of this invention to provide means to impart motion so devised that, with the parts of the motor driven means assembled in any possible relationship, the manually operable control means can be provided or not provided at the time of manufacture, or can be added to, or removed from a device already in use.

It is also an object of this invention to provide mechanical means to impart simulated movement to devices of the types listed which can be so mounted within a body that the center of gravity of the movable body, with or without a passenger, remains below the point of suspension so that the movable body tends to return to, and remain in, a vertical position after displacement from the vertical effected by the operator.

Other objects and advantages will become apparent in the following specifications when considered in the light of the attached drawings in which:

FIGURE l is a side elevation of the coin operated kiddie ride.

FIGURE 2 is a rear elevation of the motor driven mechanism.

FIGURE 3 is a plan of the motor driven mechanism.

FIGURE 4 is a right side elevation of the motor driven mechanism.

FIGURE 5 is a partial side elevation showing the relationship between the ball on the rear stanchion and the shaft of the transmission.

3,173,686 Patented Mar. 16, 1965 ice FIGURE 6 is a right side elevation showing thel cycle of the motor driven mechanism.

FIGURES 7-10-13 and 16 are right side skeletal elevations showing the cycle of the motor driven mechanism with the cranks offset.

FIGURES 8-11-14 and 17 are left side skeletal elevations showing the cycle of the motor driven mechanism with tne cranks odset. l

FIGURES 9-12-15 and 18 are front elevations show ing the cycle of the motor driven mechanism with the cranks offset.

Referring now to the drawings, in FIGURE l the recreation device is shown having in this example a b ody, drawn in dashed lines and generally indicated as B, which simulates an outboard motor boat with a small cabin; A passenger, also drawn in dashed lines and generally indicated as P, represents the largest child the seatcan comfortably accommodate, and gives by comparison relative size and location to the elements of the invention.

The horizontal base generally indicated as HB, has a steel framework base generally indicated as 1, large enough and heavy enough to resist tipping over of the device and covered by a treadplate decking 2 which. is both decorative and functional since the raised pattern is non skid and provides traction of the shoes. The base 1 is conventionally mounted on four resilient feet 3 and can be made mobile by elevating the back end which puts a pair of wheels 4 in contact with the floor. Attached to the base 1 near the back and extending up into the hollow body B is a tubular column or stanchion 21 centrally affixed to its upper end a ball 22 which is associated with a rear suspension mechanism generally indicated as S, which includes a hemispherical socket 23 attached to the body B by means of the bracket 24 and a retaining tongue 25 which is adjusted by the bolt 2e to retain the socket 23 on the ball 22 but permit universal pivotal oscillation of the socket 23 on the ball 22. A second tubular column or stanchion 31 attached to the base 1 forward of the center also extends up into the hollow body and has fixed to and extending from its upper end a generally horizontal shaft 32. Extension of the center line of shaft 32 is drawn and'indicated as CL to show that it is in line with the center of the ball 22 of the rear suspension mechanism S. It should be noted that the in line with relationship of the center line of shaft 32 and the center of ball 22 is necessary, but the center line CL need not be exactly horizontal or parallel with the base HB. lf due to the shape of a body B other than the boat in this example it is impractical to have the ball 22 at the same height as the shaft 32, it would only require that shaft 32 be attached to stanchion 31 at an angle so that the center line CL of shaft 32 is in line with the center of ball 22, whetherV the ball 22 be above or below the shaft 32. However practical considerations limit this variation `to such an extent that shaft 32. and its center line CL can always be described as generally horizonta y Referring again to FIGURE 1 and specifically to the motor driven mechanism generally indicated as M. This' mechanism M includes: a gear reducing transmission 3,5; cranks 37a and 37b (see FIGURES 2 and 3) 4attached to the ends 36a and 36h of the shaft 36 and locked by the pins 3S, crank pins 39a and 39h attached to the ends of cranks 37a and 37b and locked by the pins 40; links 41a and 411; with their bottom ends retained and journalled for rotation on the crank pins 39a and 39h respectively in beatings 42a and 42h (see FIGURES 4) and retained on but free to oscillate from the top on the shaft 32 in ends 33a and 33b of the yoke 33; the motor 43 attached to the transmission 35 and rotating the cranks 37a and 37b when energized; and a bracket 34 which zero position is shaped at the ends to t the shape of the body B and is rigidly secured to the inside of the body B by well known means such as fiberglass lamina cement. The base of the transmission 3 5 is bolted to the bracket 34. The body B isY therefore suspended between stanchion 21 and stanchion 31 and free to` be tipped or rotated with the center line CL as the axis of such movement, and free to be moved up and down in a radial arc from the center of ball 22 (see FIGURE 5) when the cranks 37a and 37b rotate.

Also shown in FIGURE l is a tipping control mechanism generally indicated as C which includes: A steering wheel 51 is secured to one end of a control shaft 52j which is journalledV for rotation in a bearing bracket 53 attached to the inside of body B. A cable 54 is wrapped several times around shaft 52, in the form of a windlass, with each end thereof leading in opposite lateral directions toand over-'opposite pulleys 55 at the upper sides of the body B and down around each of the opposite pulleys 56 at the lower sides of the body B (the pulleys are shown only in one side of the body) and secured to each free end of each of the springs 57 respectively, with the opposite ends thereof anchored on stanchion 3i, as shown.

The kind and size of the cable 54, the diameter of the shaft 52 and the strength of the springs 57 are proportioned to permit the frictional engagement of the cable 54 on the shaft 52 to tip the body B in either lateral direction when rotated in a corresponding direction by the passenger, but with insuicient friction to prevent further rotation of the shaft 52 after the body B reaches a predetermined limit angle to which it can be tipped.

It is to be noted that different control elements, such as handles and levers, may be substituted for the wheel 51 shown.

In listing the elements of mechanism M and describing their relationship to each other, no reference was made to angular relationships between these elements. It should be made clear that there are two distinct types of angular relationships between the elements of mechanism M. One is cycling in nature and is av result of the rotation of the. cranks 37a and 37b. The other is the permanent angular relationship between cranks 37a and 37b introduced. at the time they are assembled on shaft 36 and permanently establishes the pattern of the cycling change of relationship between the other elements ofv mechanism` M.

Since variation of the angular relationship between crank 37a and crank 37b is the basis of variations in thel cycling'changes between the other elements of mechanism M, it is necessary to describe rst the changes of relationship between one of the cranks 37a and 37b and the elements with which itis associated on the same side of the transmission 35. FIGURE 6, which is a composite View of one side of mechanism M- shows transmission 35, end- 36a of shaft 36, crank 37a, crank pin 39a, and link 41g in four different positions. In solid lines, the transmission 35 is shown down with the line VRLrz having at one endl an arrow pointing to the center of shaft 36 and at the other end an arrow pointing to the center of ball V 23 (see FIGURE 5). In FIGURE 6 in solid lines the crank 37a4 is shown with its center line in the center line o f transmission 35 which passesthrough the center ofshafti 36, and the crank pin 39a is shown up and having its center in the center line of crank 37a. The center line ofthe transmission 35 is generally indicated as TT and the positionof the end 36a of shaftl 36 with the center line of crank 37a., and the center of crank pin 39a in the center line 'IT of the transmission 35 is to be considered as the (see FIGURE 4v). The vertical center line through the center of shaft 33a indicated as VV shows the 'center line TT-of transmission 35 is not vertical but is tippedb forward at the top, and it also shows Y that the end36a.of. the shaft 36, the center of crank pin 39a, and the bottom of link 41a are all back of the vertical center une vv. V

In dashed lines in FIGURE 6 the position of these elements of mechanism M are shown when the shaft 36 is rotated 180 degrees from the starting or zero position. The line RLb shows that theend 36a of shaft 36 has moved up not vertically but in a radial arc, the center of which is the ball 22 (see FIGURE 5). The center of shaft 36, the center of crank pin 39a, the bottom end of link 4in and the center line TT of the transmission 35, which is now tipped back at the top, have all moved forward of the vertical center line VV. The transmission 35 has been lifted up twice the length of the throw of crank 37a, and has of course taken the body B with it.

In dotted'lines in FIGURE 6 the positions of these elements of mechanism M are shown when the shaft 36 has been rotated 9G degrees and 270 degrees from the zero position. The center of shaft 36 is in the radial arc of ball 22 shown by the line RLc, and is on the vertical center line VV. The crank 37a and the link 41a are shown in two positions which are indicated by the references 9G degrees and 270 degrees in the drawings. The link In can be observed oscillated an equal distance forward and backward from the line TT with the shaft 36 at 90 degrees and 270 degrees fromfthe zero position. The base of transmission 35 is shown as horizontal when the center of shaft 36 is in this position, but it should be pointed out that although this is the preferred mounting, the transmission V35 can be mounted with its base considerably out of horizontal when the shaft 36 is in this position.

In FIGURES 4 and 6 which are side views of mechanism M showing the crank 37a, crank pin 39a, the link 41a, and the end 36a of the shaft 36 in various positions, it was assumed but can now be clearly stated that the matching crank 37b, crank pin 3%, the link 41b and the end 3617 of shaft 36 were directly opposite. This is verified by FIGURE 2 which is a rear view of mechanism M with the shaft 36 rotated 180 degrees from the zero position and which shows the crank pins 39a and 39D down, the shaft 36 up, but the center lines of both parallel to the center lines of the yoke shafts 33a and 33h, and by FIGURE 3 which is a view of mechanism M from above which shows the center lines of the yoke shafts 33a and 33b, the center pins 39a and 39b and the shaft 36 are all parallel to each other.

With the cranks 37aV and 37b attached to shaft 36 with the crank pins 39a and. 39b in line with each other as described, and the motor 43 energized, rotation of the shaft 36 causes 'the body B to be moved up andy down in a radial arefrom the center of the ball 22 and in a plane throughthe axis CL of the shaft 32. Oscillation of the links 41a and 416 allow the cranks 37a and37b to rotate with the shaft 36 while the center of shaft 36 remains a fixed distance from the center of the ball 22. The resulting mode of movement of the body By when viewed from either end would be best described as generally vertical regardless of the lateral tipped position of the body with reference to the axis CL.

Now referring to FIGURES 7.through 18 which are skeletal views of mechanism.Mwith the cranks. 37aI and 37b attached'to the shaft 36 withV the 'crank pins 39a and 39!) not in line, and which illustrates a different and more complex mode of movement of boby B and corresponding different changes of position of the elements of mechanism M, which occur. during one revolution of shaft 36, as compared with the tirst described mode. In FIG- URE `7 the crank 37a is attached to shaft. 36V so that it is inthe zero position as previously described (see FIGURE 4).

degrees clockwise from the zerofposition Y It should be vnoted that the misalignment ofl cranks 37a and 37b is possible due to the use of ball bearing assembliesV 42a and 42h having` spherical races.. or other forms of bearings for rotation capable ofv limited universal movementrtsee FIGURE'4), which permit the Y FIGURE'Sshows the crank 37b attachedV to the Shaft 36 withV its center line advanced forty-fiveV crank pins 39a and 39h to rotate with a considerable degree of misalignment both static and dynamic with the bore of bearings 42a and 42b. The 45 degree advance of crank 37b is excessive and is used to better show the movement of the elements of mechanism M graphically. In FIGURE 9 which is a front view of mechanism M with the crank 37a at the zero position as in FIGURE 7 and the crank 37b advanced 45 degrees as shown 1n FIGURE 8, the effect of the misalignment of the cranks 37a and 37b on the other elements of mechanism M is apparent. The links 41a and 1b remain parallel vertically, the transmission 3S is tipped back at the top and turned towards the link 4l!) at the front and the center lines of crank pins 3% and 39h are not at 9() degrees from the center lines of links 41a and 41h. Referring now to FIGURE l0 in which crank 37a is shown with the shaft 36 rotated 90 degrees counter clockwise from the zero position as shown in FIGURE 7; to FIGURE 1l in which the crank 37b has advanced 90 degrees clockwise from its position in FIGURE 8; and to FIGURE 12 which is a front view with the elements in the positions shown in FIGURES l0 and 1l. It is graphically apparent by comparing the FIGURES 7, 8 and 9 with the FIGURES l0, 11 and 12. how the misalignment of the cranks 37a and 37b affects the movements of transmission 35. Study of FIGURES 13, 14 and 15 in which views of mechanism M, the shaft 36 has been rotated 1S() degrees from the zero position and FIGURES 16, 17 and 1S in which views of the mechanism M, the shaft 36 has been rotated 27() degrees from the zero position, will make apparent the complete sequence of movements of the elements of mechanism M in one revolution of shaft 36.

The resulting movement of the body B, although still radial from the center of the ball 22 is not confined to a plane through the axis CL of shaft 32 and ball 22. The movement of body B when viewed from either end can best be described as being figure eight in nature. The angle between crank 37a and crank 37b which can be varied, and is given as 45 degrees by way of example only, determines the extent and pattern of the cycle of change of angular relationship between the other elements. It is considered unnecessary to present other examples of the effect of variation in the angular relationship between crank 37a and crank 37b as it can be understood that the greater the departure of the cranks 37a and 37b from the zero position described, the greater will be the horizontal and lesser will be the Vertical movement of the mechanism M and consequently the body B. There are practical limits set by the functional capacity of such elements as bearings 42a and 42h but it is not considered necessary to develop these limits further. The best way to verbally explain the visual effect on the movement of the body B would be to say that increase of the angle between cranks 37a and 37b makes the ligure eight shorter but wider. When the body B is moving in a pattern described as ligure eight, it is to be noted that tipping of the body B on the axis CL does not affect the shape of the pattern of movement but would be like tipping the figure eight. It should also be noted that if for any reason it is desirable to eliminate the tipping of body B the yoke 33 can be pinned or permanently secured to shaft 32.

Referring now to FIGURE 1 and particularly to that part identiiied as a small cabin. Shown are the basic elements of a video mechanism generally indicated as V which presents a sequence of pictures visible to the passenger when seated at the Wheel 51 and depicting situations which the operator of an actual device, such as the body B simulates, would encounter. Switches associated with the control mechanism C and the video mechanism V would energize circuits when the passenger turned wheel 51 after each change of picture and give visual indication by means of lights on a dashboard panel and! or audio indication by buzzer or bell or other audio such as a tape player that the movement of the wheel Sil was or was not correct under the circumstances as presented by that particular picture.

As an example the pictures used in this version of the invention would consist of situations facing the operator of a boat such as meeting other boats or encountering the aids to navigation such as buoys, etc., in which situations the operator usually has three choices of action. He can continue straight ahead or turn right or left. The pictures could present situations where .only one action would be correct or they could present situations where only one action would be incorrect.

No detailed description of the video mechanism V or the circuitry to give visual indication of proficiency of an operator will be given as the mechanisms are not novel separately, or in combination, and will not be included in the claims of novelty for this invention.

Also shown in FIGURE l in dotted lines is a conventional coin box generally indicated as CB, Ithe function of which is well known. It is however, in this invention, attached directly to and made a part of the aesthetic appearance of -the body B.

This description of the mechanical operation and the manner in which our invention can be used inv this and/ or other versions makes it clear that we have provided a mechanical device which fully satisfies the objects previously stated as desirable in a device of this kind.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is as follows:

1. A mechanical device having: a horizontal base with two rigidly attached vertical stanchions; a hollow body simulating in reduced size a familar device and attached inside the said body a seat to accommodate a child passenger; a ball and a socket of matching size with the said ball firmly attached to the upper end of the first of the said two vertical stanchions and the said socket securely attached to the inside of the body and retained over but free to revolve on the said ball to a limited extent in all planes passing through the center of the said ball; a horizontal shaft extending from the side of the second -of the said two vertical stanchions which is farthest away from Ithe said iirst vertical stanchion and secured to the said second stanchion at a distance above the said base which is related to but not necessarily the same as the height at which the said ball is mounted above the said base; a yoke with a journal bearing at the center retained over and free to rotate on the said horizontal shaft and having shafts at the ends which are in line with each other; a motor driven transmission having an output shaft, said transmission being firmly attached to the inside of the said body by means of a shaped bracket and having a crank with a crank pin attached to each end of the output shaft which extends from two sides of the said transmission; a pair of links connecting the said shafts of the said yoke and the said crank pins and holding suspended the said :transmission and part of the said body to which the said shaped bracket is securely attached; and wherein the said body suspended in the one part from the said ball by means :of the said socket and suspended in the other part from the said horizontal shaft by means of the said yoke and the said links is free to move radially to a limited extent in all planes passing through the center of the said ball whether the movement be that of a generaliy vertical nature imparted by rotation of the said cranks or that movement away fnom the vertical when force exerted on the said body causes the said yoke to oscillate on the said horizontal shaft and whether these movements occur separately or simultaneously; and wherein the said suspended body has positive vertical stability so that the said body tends Ito remain in or return to the vertical position with or without a passenger in the said seat.

2. A mechanical device as claimed in claim 1 wherein the said generally vertical motion imparted to the said the vertical by adjustably Vaiiixing the said cranks to the said output shaft with the center lines of the said crank pins remainingy parallel with each other but departing from the relationship where the center line of one of the said crank pins is anl extension of the center line of the other crank pin.

3. In a recreation device of the character described a means forming a substantially horizontal base,

a first and second stanchion secured in spaced relation on said base normal thereto,

a hollow body simulating a vehicle constructed and adapted for seating a person therein, Y

a transmission means having an output shaft extending from opposite sides thereof secured in one end portion of said body with the axis of said shaft transverse thereto,

motor means connected with said transmission for driving same and rotating said shaft when energized,

a crank means including a crank pin secured Ito each opposite end portion -of said shaft,

a ball secured on the upper end of said first stanchion,

a socket means secured in the other end portion of said body engaged with said ball for limited universal pivotal motion thereon,

a support shaft secured to the upper lend of said second stanchion and positioned with the axis thereof coaxial with the center of said ball, Y

a yoke centrally journalled for oscillation on said shaft with a pair of spaced arms dependent therefrom,

a link means pivotally secured to the lower end of each of said arms for independent coaxial oscilla.- tion about an axis normal to and spaced from said support shaft,

,trasse the opposite end of each saidA link means journalledy for rotation on each of said crank pins respectively whereby said body is secured for pendulous lateral oscillatory movement about the axis of said support shaft in opposite directions from a central level position.

4. The construction recited in claim 3 including the said crank means secured to each opposite end` portion of said shaft with the axis of each o-f said pin in coaxial relation and in parallel spaced relation to said output shaft whereby said body will be vertically oscillated Vabout the center of lsaid ball independent of the said lateral oscillatory movement of said body when said motor is energized.

5. The construction recited in claim 3 including the said crank means secured to each opposite end portion of said shaft with the axis of each of said pin in parallel relation and in predetermined angular displacement from each yother with respect to the axis of said shaft whereby said body will be oscillated in predetermined both vertical and lateral movement about @the center of said ball when said motor is energized.

References Cited bythe Examiner UNITED STATES PATENTS 872,627 l2/O7 Keen 272-17 2,680,019 1/54 Bastian Y272--1 2,9313 16 5/60 Bradstreet 272-17 FOREIGN PATENTS 421,309 12/34 Great Britain.

RCHARD C. J'IfJKkLeilvI, Prmm'y Examiner. 

1. A MECHANICAL DEVICE HAVING: A HORIZONTAL BASE WITH TWO RIGIDLY ATTACHED VERTICAL STANCHIONS; A HOLLOW BODY SIMULATING IN REDUCED SIZE A FAMILAR DEVICE AND ATTACHED INSIDE THE SAID BODY A SEAT TO ACCOMMODATE A CHILD PASSENGER; A BALL AND A SOCKET OF MATCHING SIZE WITH THE SAID BALL FIRMLY ATTACHED TO THE UPPER END OF THE FIRST OF THE SAID TWO VERTICAL STANCHIONS AND THE SAID SOCKET SECURELY ATTACHED TO THE INSIDE OF THE BODY AND RETAINED OVER BUT FREE TO REVOLVE ON THE SAID BALL TO A LIMITED EXTENT IN ALL PLANES PASSING THROUGH THE CENTER OF THE SAID BALL; A HORIZONTAL SHAFT EXTENDING FROM THE SIDE OF THE SECOND OF THE SAID TWO VERTICAL STANCHIONS AND SECURED AWAY FROM THE SAID FIRST VERTICAL STANCHION AND SECURED TO THE SAID SECOND STANCHION AT A DISTANCE ABOVE THE SAID BASE WHICH IS RELATED TO BUT NOT NECESSARILY THE SAME AS THE HEIGHT AT WHICH THE SAID BALL IS MOUNTED ABOVE THE SAID BASE; A YOKE WITH A JOURNAL BEARING AT THE CENTER RETAINED OVER AND FREE TO ROTATE ON THE SAID HORIZONTAL SHAFT AND HAVING SHAFTS AT THE ENDS WHICH ARE IN LINE WITH EACH OTHER; A MOTOR DRIVEN TRANSMISSION HAVING AN OUTPUT SHAFT, SAID TRANSMISSION BEING FIRMLY ATTACHED TO THE INSIDE OF THE SAID BODY BY MEANS OF A SHAPED BRACKET AND HAVING A CRANK WITH A CRANK PIN ATTACHED TO EACH END OF THE OUTPUT SHAFT WHICH EXTENDS FROM TWO SIDES OF THE SAID TRANSMISSION; A PAIR OF LINKS CONNECTING THE SAID SHAFTS OF THE SAID YOKE AND THE SAID CRANK PINS AND HOLDING SUSPENDED THE SAID TRANSMISSION AND PART OF THE SAID BODY TO WHICH THE SAID SHAPED BRACKET IS SECURELY ATTACHED; AND WHEREIN THE SAID BODY SUSPENDED IN THE ONE PART FROM THE SAID BALL BY MEANS OF THE SAID SOCKET AND SUSPENDED IN THE OTHER PART FROM THE SAID HORIZONTAL SHAFT BY MEANS OF THE SAID YOKE AND THE SAID LINKS IS FREE TO MOVE RADIALLY TO A LIMITED EXTEND IN ALL PLANES PASSING THROUGH THE CENTER OF THE SAID BALL WHETHER THE MOVEMENT BE THAT OF A GENERALLY VERTICAL NATURE IMPARTED BY ROTATION OF THE SAID CRANKS OR THAT MOVEMENT AWAY FROM THE VERTICAL WHEN FORCE EXERTED ON THE SAID BODY CAUSES THE SAID YOKE TO OSCILLATE ON THE SAID HORIZONTAL SHAFT AND WHETHER THESE MOVEMENTS OCCUR SEPARATELY OR SIMULTANEOUSLY; AND WHEREIN THE SAID SUSPENDED BODY HAS POSITIVE VERTICAL STABILITY SO THAT THE SAID BODY TENDS TO REMAIN IN OR RETURN TO THE VERTICAL POSITION WITH OR WITHOUT A PASSENGER IN THE SAID SEAT. 